I. Field of the Invention
The present invention relates to vehicle monitoring and control systems. More specifically, the present invention relates to a novel and improved method and apparatus for detecting fault conditions within vehicle data recording devices.
II. Description of the Related Art
Recently, trucking and delivery vehicles have been equipped with a variety of electronic sensors and monitoring devices. Such instrumentation may be utilized to monitor parameters such as vehicle speed, engine speed (RPM), and fuel consumption. The data accumulated by these and other on-board vehicle sensors will typically be directly provided to a vehicle recording device. As an alternative, vehicle operational and performance data may be collected by other vehicle electronic units disposed to monitor vehicle sensors. The collected data is then transferred to the recording device over an internal vehicle data link.
The accumulated data within the on-board recorder is periodically transferred, or "downloaded", to a host processing facility or central control center. This transfer process has hitherto been performed by manually disengaging the recording device from the vehicle and accessing it within the host facility. Unfortunately, such manual data transfer requires either that each vehicle within a fleet periodically visit the host facility, or that other arrangements be provided for physical transport of the recording device. Besides being inconvenient, such manual data transfer techniques prevent timely updates from being made to databases used for fleet management and control.
It is also known that hardware failures within the vehicle sensing and data recording apparatus may result in errors being introduced into the accumulated vehicle data. For example, if an electrical system failure were to cause the recording device to become temporarily disconnected from the main power source, the resulting loss of vehicle sensor data would typically lead to underestimation of a number of operational parameters (e.g., miles logged, fuel consumption, and engine run time).
As a consequence, vehicle fleet operators have often been forced into performing extensive monitoring of the sensor data acquisition process as a means of verifying data integrity. Given that data collected by vehicle recording devices is often used as a measure of driver performance, there exists an incentive for drivers to tamper with or otherwise temporarily disable the data recording device. Accordingly, there is an interest not only in the detection of genuine hardware faults within vehicle sensing and data recording apparatus, but also in the identification of incidents of operator tampering or device disablement. Since under certain circumstances intentional tampering may be even be more difficult to detect than actual hardware faults, a need exists for even more sophisticated data verification measures.
Accordingly, it is an object of the invention to provide a diagnostic procedure for detecting hardware faults within on-board vehicle data recording systems.
It is another object of the invention to identify instances of tampering with such on-board recording systems.
It is still a further object of the invention to provide for real-time reporting of accumulated on-board vehicle operational data and fault conditions to a central or host processing facility.